When I think of the tens of thousands of miles of logging roads that are no longer maintained, there should be no shortage of roads for you to find. Larch Mountain and Table Mountain area come to mind.

Then again, you may be thinking of less rural settings.
Forest Park has a series of roads that were once residential.
The Old Columbia River Highway sections have been updated as a bicycle trail during the past decade, which has ruined the photographic integrity of the roadways.
The convict highway (former SR-14) on the Washington side has several sections that might be relevant.
Rails to Trails could be another way to go.
Laurel Hill (hwy 26) was mentioned earlier.
Hwy 35 (south of Barlow Pass) is another one that comes to mind.
Sections of Hwy 101 along the rocky headlands might be of interest with the best sections being in Boardman and the Redwoods to the south.

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